This study quantitatively examined the effect of block scheduling on student achievement. Specifically, the study compared student achievement as measured by the Pennsylvania System of School Assessments (PSSA) Reading and Math exams between students in block scheduled schools and traditionally scheduled schools. The sample for this study included over 53,000 individual student scores from public high schools in the south central region of Pennsylvania. The data sets used for analysis included individual student test results from the 2003, 2004 and 2005 administrations of the 11^th grade PSSA Math and Reading Exams. This study utilized a hierarchical linear model analysis to examine the effects of school schedule type while attempting to control for student and school level variables. The dependent variables for level one were: IEP status, LEP status, economically disadvantaged status, gender and ethnicity. The dependent variables for level two were: school setting, percentage of economically disadvantaged students, and schedule type. Analysis of the data indicated that school schedules had no statistically significant impact on student achievement scores after controlling for student and school level variables. The study included an extensive literature review and implications for further research both nationally and in Pennsylvania. Contains 90 references.